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W3MIV
10-03-2010, 08:56 AM
My first HF antenna at this QTH was a 90' wire tuned by an ICOM AH-4 auto tuner. The trees were small, all outdoor antennae verboten, and stealth was the name of the game. The tuner was mounted to the wall outside, just above the basement shack, and though it was rated for 80 thru six, it worked surprisingly well on 160 -- though highly directional. All went fairly well until the aluminum siding was replaced by vinyl; all manner of bizarre RF issues suddenly intervened.

The trees having grown, as trees are wont to do, I decided to put a wire dipole up in place of the AH-4. Casting about for a design that would fit and be well hidden from the antenna nazis, I pored over the ARRL antenna compendia in search of some magic solution to my lot and my desires to reach as low on the bands as possible.

I decided to try Louis Varney's ubiquitous G5RV. A host of complications badgered me -- the 34' feed line was much longer than I could manage and the wire itself was a bit long for the only spot I had that would hide it.

Irv (I cannot now remember his call, but he was the QRZ curmudgeon from Sacramento who lurked in the Q&A forum waiting a chance to pounce upon the innocently ignorant awardees of modern licenses, skewering them for their lack of technical prowess) put me on the griddle about the G5RV and kept insisting that I read up on "conjugate matching." I confess, at the time, I thought he was citing a marriage manual.

I was led, by the nose perhaps, to obtain a copy of "Reflections," Walt Maxwell's (W2DU) classic treatise on transmission lines and antennae, and Mr Maxwell led me to understand that those dreaded SWRs that threaten one's peace and sleep are highly over-rated as gremlins waiting to destroy one's station. If there is any single book that has influenced my on-going development as an amateur, I would put Reflections at the head of the list.

I put 100' of insulated, 12ga wire into the trees, fed it with twisted 300Ω window line cut, not to some length from a wavelength table, but merely to fit the distance needed, attached a 1:1 current balun and made the final entry with a minimal length of coax. That antenna, with a good transmatch, works well from 80 through ten, yielding good performance -- though, as with any multi-band dipole, the lobes vary and coverage changes around the rose; also, I cannot get the antenna high enough to achieve a really low launch angle. Compromise is a large part of what I have to do.

My first rig was an IC-725, and I used an old Heathkit 2060a tuner. Antenna performed like a champ. Growing a bit bolder, I bought a used IC-746Pro and shipped it off to Bellevue WA and had the techs at ICOM wring it out and bring it up to spec (ICOM would update any rig still in production free-of-charge). I swapped out the Heath tuner and substituted Martin Jue's fine 993B auto-tuner. The antenna continued to perform flawlessly. Finally, I retired the 746 and brought in a brandy new 756ProIII and added an AL80B with a full-limit Versa-Tuner (both of which I rarely use -- I bought the amp specifically to work Peter I Island but ended up doing so barefoot).

A bit over two years ago, my neighbor's Bradford Pear tree invaded my fenceline during a storm, taking out the antenna mast, snapping the dipole legs and supports, and bringing the entire system down in a tangle.

I have now replicated the antenna, and I hope shortly to have it back in the air. Alas, my schedule is complicated and crowded at present, so I cannot predict when I will be ready. I look forward to meeting some of you on the air; I will post on the sked forum when I can.

PA5COR
10-03-2010, 09:17 AM
Hope to find you back in the air soon.

Not much trouble with antenna nazi's, but since i know our law too well, i ironed out the kinks i thought i would get, resulting in the mayor and his merry men to be very forthcomming with helping us hams out.

The housing firm renting out this house had a whiff of a try to get my antennna's gone, after a 23 page defense with all laws explicitely named and an demand of 500 euro a day if they removed my stuff, i never heard from them again, just that the person that started the action was laid off.

Life can be beautifull...
;)

Take care, good luck putting up a good system.

WØTKX
10-03-2010, 09:20 AM
That ROCKS, Albi! :bbh:

I too am amazed at the silliness over SWR's. It's what gets radiated that counts... :mrgreen:

WX7P
10-03-2010, 09:32 AM
Irv (I cannot now remember his call, but he was the QRZ curmudgeon from Sacramento who lurked in the Q&A forum waiting a chance to pounce upon the innocently ignorant awardees of modern licenses, skewering them for their lack of technical prowess) put me on the griddle about the G5RV and kept insisting that I read up on "conjugate matching." I confess, at the time, I thought he was citing a marriage manual.


That would be Baby (H)UEY K6UEY, my neighbor to the South of the Tomato.

Great story!

WØTKX
10-03-2010, 09:36 AM
Heheh, I've talked to that silly son of a... heheh.

NQ6U
10-03-2010, 12:07 PM
Good story, Albi, nice to see you can write as well about ham radio as you can about politics! I am relatively lucky in that my home burg is lenient about allowing antennas, my only restriction being the XYL veto. I am gradually wearing her down, though.

I too learned a lot from reading "Reflections," and I would recommend it to any amateur radio operator. I have a PDF of it and would be happy to send a copy to anyone who wants one. Just PM me with your e-mail address.

So, get that antenna up ASAP, Albi--I'd love to have a QSO with you one of these days. My station (http://www.eham.net/spotlight/spotdetail/0be77a53de0195c2837b9f37c040b630) is also very modest but it gets out very well on 20m, especially in the PSK31 mode.

W3MIV
10-03-2010, 02:04 PM
At one time, I worked digital modes almost exclusively, and I packed a bunch of log entries in PSK31 and RTTY. In fact, I am an early member of the European PSK club, holding number 59 in that august body. Variations in typing abilities, however, gradually began to irritate me. Some guys could never figure out that you could type ahead, building an entire reply as you read the lines screening up. Watching one letter slowly appear after another became tiresome. I gradually fell away from twenty for PSK because of the "wham, bam, thankee ma'am" contacts that obviated long, chatty QSOs -- which, to my mind (as a raconteur and bullshit artist), are the raison d'etre of amateur radio. Seventeen and forty are far more pleasant.

Thanks, Dave, for reminding me of UEY. I got his name close, but no cigar. As I now remember, it was Orv, not Irv. Irascible sucker, but knowledgeable and his style, though obnoxious, forced you to think a process out. He would not give easy answers. Never had the pleasure of a QSO, though. Wonder if he's still giving 'em hell over there.

N8YX
10-04-2010, 07:19 AM
Thanks, Dave, for reminding me of UEY. I got his name close, but no cigar. As I now remember, it was Orv, not Irv. Irascible sucker, but knowledgeable and his style, though obnoxious, forced you to think a process out. He would not give easy answers. Never had the pleasure of a QSO, though. Wonder if he's still giving 'em hell over there.
Sadly, no. With the new "kinder, gentler" incarnation of the place, inflammable commentary is no longer condoned.

Mr. Maxwell's observations regarding transmission-line radiation, balanced feedline and a load which is much shorter than an electrical 1/2 wavelength are in error - the underlying physics having been substantiated by myself and a couple other ham/RF engineer friends. Given the fact that no one dares piss on "their golden boy" these days, I will refrain from replying to select comments by Walt in a number of threads. Some of which even witnessed 'GQ getting the answer correct but nevertheless being "silverbacked" off to the sidelines ... :roll:

W3MIV
10-04-2010, 07:37 AM
Mr. Maxwell's observations regarding transmission-line radiation, balanced feedline and a load which is much shorter than an electrical 1/2 wavelength are in error - the underlying physics having been substantiated by myself and a couple other ham/RF engineer friends. Given the fact that no one dares piss on "their golden boy" these days, I will refrain from replying to select comments by Walt in a number of threads. Some of which even witnessed 'GQ getting the answer correct but nevertheless being "silverbacked" off to the sidelines ... :roll:

While I don't intend to get into a major argument, I have used Maxwell's 90'-100' dipole fed with 300Ω window line cut to minimum dimension needed to fit the site and it has worked for me on 80 precisely as he indicated it would. I confess that I have neither the background nor the equipment to make sophisticated analyses of his work, but the practical results I have obtained verify his recommendation. Forgive my bluntness, but I shall stick with him.

N8YX
10-04-2010, 07:54 AM
While I don't intend to get into a major argument, I have used Maxwell's 90'-100' dipole fed with 300Ω window line cut to minimum dimension needed to fit the site and it has worked for me on 80 precisely as he indicated it would. I confess that I have neither the background nor the equipment to make sophisticated analyses of his work, but the practical results I have obtained verify his recommendation. Forgive my bluntness, but I shall stick with him.
Which it will, because the radiator in question isn't substantially shorter that a half wavelength at the desired frequency. Now try that trick with, say, a 50-foot (overall) dipole and it'll still work after a fashion...but...at 'low' (3-4 MHz and below) frequencies, the feedline will comprise part of the antenna. This is the point of contention I speak of - Maxwell claims the feedline won't radiate under such conditions and a number of folks (including myself) opine that it will...

N8YX
10-04-2010, 07:57 AM
By the way: Willie Hotel is having problems assembling a lowly 9-element VHF array. Anyone here feeling generous enough to help a brother out?

http://forums.qrz.com/showpost.php?p=2055389&postcount=1

PA5COR
10-04-2010, 12:51 PM
Nope.

kf0rt
10-04-2010, 12:56 PM
Sorry. I need to sort my sock drawer. :hand:

WØTKX
10-04-2010, 01:02 PM
Washing my imaginary hair.

NQ6U
10-04-2010, 01:02 PM
Going in for a root canal instead. More enjoyable.

W3MIV
10-04-2010, 01:17 PM
Too bad we can't watch, though. :evil:

NQ6U
10-04-2010, 01:43 PM
Too bad we can't watch, though. :evil:

I'm having made available as live video streaming. $10 subscription, though--I don't have dental insurance and I need to pay for the procedure.

W3MIV
10-06-2010, 05:02 AM
I now have the antenna complete and ready to go into the branches. Got out the ol' MFJ 259B and charged up the batt-ries. Now looking for a bit of time in my schedule to erect the mast (at my age I get a tingle just using that word!); once that bit of carpentry is done, pulling the wires into place should be fairly simple (he said with a prayer).

Won't be long before I hope to be in the sked forum. I especially like forty, thirty and eighty. Twenty is great when it's there -- but I have a feeling that pump will be sucking air for some time to come.

W3MIV
10-07-2010, 07:06 PM
The antenna is now in the trees. Not as high as I would like, but the damned trees are too dense, and there are too many leaves to deal with. Maybe later in the winter, if we don't have snow up to a musk ox's butt, maybe I can work it higher once the damn leaves are down.

It works. Hard to tell how well, because I have not had time to do any real tests. Too tired to do it, now. Mañana.

Only worked PSK for a while this evening, and only on twenty. Lower bands were lots of noise; didn't check thutty. Cuba, Florida, Alabama, Spain and British Columbia -- a total of six contacts via PSK31. Lots of gray-line stuff coming up SA, hot Columbia and Brazil among others this evening, and out of N EU, but I was dividing my time between the rig and fixing dinner. :roll: Ah, domesticity has its own rewards. I guess.

Mañana. There's always another day. I hope!

W1GUH
10-08-2010, 12:25 PM
Albi, lose the balun and get (or build -- they're very, very easy to make. K1JJ's design (http://amfone.net/ECSound/K1JJ13.htm) is a classic.) a real, link-coupled matching network. The low power Johnson Matchbox is pretty common at hamfests for $50-100.

OTOH...the difference will probably never be heard on the receiving end, so, that's pretty much an OF habitual rant!

And, as for "antennas are verborten", au contraire my friend. I seriously doubt that they'd object to, or even notice, a hamstick mounted on your car. Run the coax into the shack and viola! a decent-performing (especially on 20 and above)vertical, hidden in plain site! They're almost trivial to mount on a car using the Diamond K-400 (http://www.universal-radio.com/catalog/hamantm/0978.html).

Now that I've gotten that off my chest...hows about a sked Sunday as I'm driving up to or home from (or both) the Wallingford hamfest? I'm guessing 40'd be good...we could meet up on ecars (7255) or midcars (7258 ) if they're active then. If Sunday's NG for you, how about Sat. on my way to or from the Bergen County hamfest? And you can hear how well hamsticks perform.

Have fun back on the air!

Hmmmm....Ham Island software must think midcars is really, really cool. If I don't a space before the right parenthesis, it looks like (7258) !! :hyper:

W3MIV
10-08-2010, 12:56 PM
Sure, Paul. Give me a time when you want to give it a shot. LSB on forty would work I think, though I have no idea where Wallingford is. NJ?

7255 sounds good, though I am not an ECARS person -- I guess they'll let me check in. I can go pretty near anywhere for phone.

I don't do mobile. Have a couple of 2m rigs, Kenwood 761A and a Yaesu 1802, but rarely put them in the car. Car, BTW, is a Crown Vic with a black grill -- when I mount the antenna on the NMC in back, nobody thinks to stop me. ;)

The balun is a 1:1 current type -- basically a bunch of chokes around the coax -- that keeps RF off the shield and forces the two lines of the ladder to play nice. I run coax from the balun those last several feet into the shack. MFJ autotuner handles barefoot 756ProIII very well, and I have a MFJ 989D on a separate antenna feed that tunes the AL80B on those rare occasions when I need a bit of help. The linear, however, is a PITA in comparison with the MFJ 993B autotuner -- which is fast as lightning when changing bands -- a big plus in a contest.

I have been tuning around and testing -- today worked France, Belgium and Iceland on twenty PSK, and the South and Southwest on 30m, PSK.

W1GUH
10-08-2010, 01:01 PM
Excellent!! Wallingford's in central CT. I know of at least one other Islander who's going to be there...maybe more, I haven't checked "Hamfest Calendar" lately.

Both days I'll probably get on the road about 7:00 AM and have the mobile going about 7:30. I wait til I'm out of the city to set it up. Wallingford's about 2 hours away and Bergen County's about hour away. Just to say a time, make it 8:00 AM. Either service will be more than happy to help us hook up -- that's one of the primary purposes for their existence. That's usually my first choice because if the band is lousy and we can't hear each other, somebody can relay if only to let us know condx suck!

I'm looking forward to the euphonious sound of your voice!

W3MIV
10-08-2010, 01:28 PM
OK, Paul. I just checked in with ECARS just to make sure I can communicate. W2PSU working the net out of Vermont; clear QSO and lot of traffic, so I will be able to work you and anyone else who wants to hear my croak. 0800 will work fine for me, I am an oily riser.

Hooe to QSO with you then.


Excellent!! Wallingford's in central CT. I know of at least one other Islander who's going to be there...maybe more, I haven't checked "Hamfest Calendar" lately.

Both days I'll probably get on the road about 7:00 AM and have the mobile going about 7:30. I wait til I'm out of the city to set it up. Wallingford's about 2 hours away and Bergen County's about hour away. Just to say a time, make it 8:00 AM. Either service will be more than happy to help us hook up -- that's one of the primary purposes for their existence. That's usually my first choice because if the band is lousy and we can't hear each other, somebody can relay if only to let us know condx suck!

I'm looking forward to the euphonious sound of your voice!

W1GUH
10-08-2010, 01:36 PM
Before I put my brain in gear and figured out it was a typo, I googled "hooe". You're always a good source for new vocabulary, so what the hey? Theres a family actually named that!

I forgot the flip side. I expect to leave both of them about 11:00 AM, but whether or not I do leave then, I'll check in from the parking lot at that time - so there's a second chance in case condx are bad in the morning.

Happy operating! It's such a nice thing to finally get back on the air!

BTW...everyone else feel free to drop in!

W3MIV
10-08-2010, 01:39 PM
Typo. See, I really am fallible after all. Don't spread it around.

I just posted our sked on the sked thread. Maybe we can get more Islanders to join in. As I said there, we can always shift up some away from ECARS and away from the PA QSO Party. I can easily keep linked to the Island and post our whereabouts.

Will be fun. Looking forward to it!


Before I put my brain in gear and figured out it was a typo, I googled "hooe". You're always a good source for new vocabulary, so what the hey? Theres a family actaully named that!

I forgot the flip side. I expect to leave both of them about 11:00 AM, but whether or not I do leave then, I'll check in from the parking lot at that time - so there's a second chance in case condx are bad in the morning.

Happy operating! It's such a nice thing to finally get back on the air!

BTW...everyone else feel free to drop in!

NQ6U
10-08-2010, 01:43 PM
Alas, 05:00 local is a bit early for this boy on a Saturday. But, the way I've been sleeping lately (hardly at all), I wouldn't dismiss it out of hand.

W3MIV
10-08-2010, 01:49 PM
Alas, 05:00 local is a bit early for this boy on a Saturday. But, the way I've been sleeping lately (hardly at all), I wouldn't dismiss it out of hand.

We were originally talking about Sunday, but Saturday works as easily. I will be there for either or both. I am awake shortly after five every morning of the week. Old men get that way ;)

It's a special occasion, and you ortta give it a shot. Don't know how prop to the Left Coast will work, but I can add some heat if I am weak. If I can hear you, I can likely work you. But, of course, that remains to be seen.

W1GUH
10-08-2010, 02:39 PM
Alas, 05:00 local is a bit early for this boy on a Saturday. But, the way I've been sleeping lately (hardly at all), I wouldn't dismiss it out of hand.

I'll check out 20 - maybe even 17 or 15 at 1500Z both days. Somewhere roundabout 14.275. I'll do a few CQ's.

KJ3N
10-08-2010, 04:01 PM
Somewhere roundabout 14.275. I'll do a few CQ's.

Oh, that'll be real entertaining.... :rofl: :rofl: :rofl: :rofl:

W1GUH
10-10-2010, 01:38 PM
Albi, I was on 40 yesterday at 7:30 but I don't think the band had woken up yet, or at least was lousy for the hop from NNJ to where you are. It was open further south, but I think was too long for us. Later in the morning it was good pretty much all up and down the eastern seaboard. This morning I was distracted making a deal for a TR-7 (see the hamfest board). Mil pardon, monsieur. Another time? I'm pretty sure I'll be on the road with my new-old radio!

W3MIV
10-10-2010, 05:30 PM
Not a problem, Paul. I called three times over about ten or twelve minutes this morning on 7255 from 0800; there were still some BC stations and carriers, so it likely was long. Forty was pretty crappy working the PA QSO -- 75 was a whole lot better, even as the day wore on. I ended up working some PSK on twenty and seventeen, and even added Uzbekistan -- a new one for me -- this afternoon.